A 16-slice multidetector computed tomography protocol for evaluation of the gastroepiploic artery grafts in patients after coronary artery bypass surgery

Abstract

Arterial coronary bypass grafts [internal mammary arteries and gastroepiploic artery (GEA)] are in widespread use for coronary surgery. Since selective catheterisation of the GEA graft to monitor patency, is often unsuccessful, a non-invasive protocol to visualise the GEA-graft from origin to anastomosis is presented using 16-slice multidetector computed tomography (MDCT). Twenty-six male patients (mean age 58.1+/-6.7 years) with GEA grafts were scanned according to a protocol of an ECG-synchronised cardiac scan followed by a thoracoabdominal scan. To terminate the scan at the correct anatomical level, the lowest level of the GEA was coded based on the lumbar vertebrae level. Scores ranging from one (excellent) to four (bad) were assigned to evaluate visualisation quality of the grafts. GEA grafts were assessable in 62% of the thoracoabdominal scans and 69% of the cardiac scans. On average, the lowest part of the GEA corresponded with a level between L1 and L2, in two cases in the upper part of L3. Mean visualisation score in the thoracoabdominal scans and cardiac scans was good (respectively 1.4+/-0.6 and 1.4+/-1.0). Sixteen-slice MDCT is a promising alternative for catheterisation in evaluating patency of GEA grafts, using the presented protocol with thoracoabdominal scan including L3 for complete coverage of the GEA graft.